Center Filter Needed for 90mm on 4x5?

[HughC]

Is a center filter a must for 90mm lens on a 4x5 Field camera.

[Doremus Scudder]

Is a center filter a must for 90mm lens on a 4x5 Field camera.

Depends on your needs and capabilities.

Many who work only in black-and-white don't bother with a center filter for 90mm and even shorter lenses on 4x5. Instead, any balancing of fall-off that is needed gets done during printing. Same with color negative film for many; fall-off gets corrected when printing or in post. Important here, of course, is to realize the the edges of the image circle will get less exposure than the center and to give adequate exposure when needed to ensure the shadow detail at the extremes of the image circle.

Where center filters are considered more necessary is when working with color transparency materials. With these, there is no possibility for dealing with the fall-off unless one scans and digitally post-processes. Still, with the more limited dynamic range and latitude of transparency film, that's often not a good solution either.

Not using a center filter also means you can use the filter size that fits your lens when filters are needed. Many center filters step-up the filter size to a larger one to prevent vignetting. This means you'll need a set of larger, more-expensive filters.

FWIW, I have never used a center filter on either 90mm or my 75mm lenses. I've perfected what I call a "center burn" that I use in the darkroom while printing. Basically, it's just "zooming" a card with a hole cut in the middle up and down over the optical center of an image that exhibits unwanted fall-off.

Best,

Doremus

[xkaes]

This has been discussed a lot on this FORUM. You can use the SEARCH feature (upper right-hand corner of this screen) to view these.

Like many options/choices/decisions in photography, it's easy enough to test for yourself. You are the judge:

http://www.subclub.org/fujinon/center4.htm

[Kiwi7475]

In a nutshell, for color negatives or slides it is a must for me. For b&w it is not. Can you get away without it? Most times yes. Also if you scan the negatives you can also correct it in digital in most but the most extreme cases.

[Drew Wiley]

It's both an esthetic choice and a technical one. Depends on the look you want, the film type, and how you intend to reproduce the image. I personally used one for both black and white and color film with a 90mm lens. These are most typically a stop and a half of neutral density for that focal length. Even with color neg film you can potentially get falloff color crossover issues in the corners without CF correction. And that kind of issue can't be corrected by simple dodging and burning, or easily if at all digitally either. Just be aware of it. Whether it matters to you or not is a separate question.

[xkaes]

Like many options/choices/decisions in photography, it's easy enough to test for yourself. You are the judge:

http://www.subclub.org/fujinon/center4.htm

[Alan Klein]

Keep in mind that center filters add to the size required for other filters like a polarizer or contrast filters for BW.

[xkaes]

Keep in mind that center filters add to the size required for other filters like a polarizer or contrast filters for BW.

Keep in mind that center filters can be added AFTER filters like a polarizer or contrast filters for BW.

There is no law against it where I live anyway

[Martin Aislabie]

I shoot b&w and bought a CF for use with my 90mm lens.

However, I tried with and without and although there is a difference, I found it not to be worth it.

So, in answer to is it a MUST - then for b&w the answer is no - but it is a nice to have.

I do use the same CF with a 65 and 47 mm lenses and I put the CF after the coloured filter.

Martin

[Drew Wiley]

I had no problem at all using a same size standard contrast filter behind the wider center filter itself. No optical issues at all. It is hypothetically possible, doing so, that you might get a little mechanical vignetting with some extreme rise or similar movement movement using a very wipe aperture - never happened to me, or is likely too in ordinary applications. CF's don't even work properly at wide apertures; so putting them in front of another filter is a non-issue; they're designed for usage around f/16 to f/22 or so.

[Alan Klein]

Keep in mind that center filters can be added AFTER filters like a polarizer or contrast filters for BW.

There is no law against it where I live anyway

The center filter probably will vignette if you place it after the other filters. Plus the CF is designed to falloff properly when placed right after the lens, not further away.

[Drew Wiley]

No it won't, Alan, at least in the case you and I know about. I've tested for every big of that, right down to center to edge density tests. And I've even used CF's designed for WA camera lenses on enlarger lenses. But if someone stacked several filters under one, that would probably be a different story. In certain cases, like the 120 Super Angulon, you have to have an intermediate spacer ring or the bulging front of the lens will make contact with the back of the CF filter glass.

[xkaes]

Just do what Copernicus did -- test.

[Drew Wiley]

Yeah, but you risk getting burned at the stake if you tell others the results.

[xkaes]

That's all?

[Alan Klein]

No it won't, Alan, at least in the case you and I know about. I've tested for every big of that, right down to center to edge density tests. And I've even used CF's designed for WA camera lenses on enlarger lenses. But if someone stacked several filters under one, that would probably be a different story. In certain cases, like the 120 Super Angulon, you have to have an intermediate spacer ring or the bulging front of the lens will make contact with the back of the CF filter glass.

So the Nikkor 90mm f4.5 takes an 82mm filter without the CF and the CF requires 107mm filters. So if I bought an 82mm polarizer (the thinnest I suppose) I should be able to place the CF on the polarizer filter and shoot color without vignetting? Ditto with contrast filters and BW shooting?

Of course, the other main issue is graduated neutral density filters. They have to be over 107mm since it seems the CF must be on first. Right?

[Alan Klein]

Just do what Copernicus did -- test.

Too expensive to buy and try it out.

[Drew Wiley]

Alan -polarizers are double-element, so especially thick. The angle of view of a 90 is pretty wide, and might lead to uneven polarization itself anyway. And those slide-in adapters for rectangular grads are too thick to be behind a CF. What I said was fine to do was to use a basic round glass 82mm filter behind the CF for the 90/4.5 SW, whether a b&w contrast filter of some kind of color correction filter like a Skylight or UV. Bu stacking a bunch of other stuff in the optical path baffles me anyway, and seems counterproductive, especially the notion of using a center filter and a rectangular ND grad at the same time.

[SergeyT]

The 90mm F4.5 SW covers 5x7.
On 4x5 the light fall off at any practical for landscape aperture is almost undetectable.
I have never used a CF with it and never will even if someone gives it away for free :)

[Lachlan 717]

I used polarisers between lens and CF on both 72mm and 90mm. No issues at all with either.

I’ve got a test using the 72mm with and without CF on Velvia somewhere; I’ll have a look tomorrow and try to do a scan of both. (Spoiler - it made a HUGE difference and I wouldn’t shoot the 72mm without it. YKMV…)

[Tin Can]

I do not shoot color sheet film

and I like the automatic vignetting on BW

I think ALL center filters are imperfect by now...

[Alan Klein]

I do not shoot color sheet film

and I like the automatic vignetting on BW

I think ALL center filters are imperfect by now...

What do you mean, "...by now."

[Drew Wiley]

Sergey - you and my densitometer don't agree about that falloff on 4X5 "not being detectable" - not by a country mile. This is especially the case if a greater portion of the image circle is used, like the common use of significant rise in architectural photography. In that case, it's easily the full stop and a half of the prescribed CF exposure compensation. That's a helluva lot when it comes to repro of color images, especially chromes. And landscape work itself can often involve serious rise and movements. Just spend some times in our redwood forests or among the the high peaks. And plenty of times "architecture" and "landscape" intersect, or occur on the same trip; there aren't nice neat pigeonholes one can lump this or that into every time, thank goodness. All that kind of terminology gets pretty crass.

Black and white photography - don't make assumptions either. A high contrast scene of 10 - 12 stop range might not have any latitude left on the film for retrieving shadow detail, depending on the specific film involved. Of course, if one enjoys totally blacked out corners to the image, that's their choice.

[SergeyT]

Drew,

I shot a lot of images with a Chamonix. That thing does not allow much of movements with a 90mm lens. I have yet to see my imagens failing due to excessive light falloff with that lens on a monorail with significant rise or fall.
Usage of a densitometer moves this discussion into scientific realm. Scientific research is not the purpose of my photography.
There always will be edge cases where usage of a CF with the 90mm F4.5 SW might be beneficial. For general photography the benefits of it are questionable but the associated pain is not. Hence my earlier statement.
I will not make the same statement about usage of a CF with other 90mm lenses as I have no experience with them. Super Angulons of 75mm and wider do greatly benefit from usage of a CF up a point where the light falloff is quite pronounced and requires corrections even on 6x12.

[xkaes]

Sergey - you and my densitometer don't agree about that falloff on 4X5 "not being detectable" - not by a country mile. This is especially the case if a greater portion of the image circle is used, like the common use of significant rise in architectural photography. In that case, it's easily the full stop and a half of the prescribed CF exposure compensation.
237649

I use a WEAK CND filter on my 105mm lens because the corners -- with its 80° picture angle -- has a 1.5 f-stop light fall off in the corners.

Some people like light fall-off, some don't -- and other don't notice it. And a lot depends on the subject.